PDMDAAC合成工艺研究进展

对聚二甲基二烯丙基氯化铵(简称PDMDAAC)合成工艺研究进展进行了综述。在系统介绍PDMDAAC合成方式的基础上,以应用最为广泛的水溶液聚合法为主线,详细介绍了其国内外研究工作的发展历史与现状及代表性工艺。归纳讨论了在聚合反应过程中影响产物相对分子质量大小(以特征黏度计)的诸因素,如:单体所含杂质种类及质量分数、引发剂种类、聚合工艺条件等。最后,对PDMDAAC合成工艺研究及相关工作的前景作了展望。引用文献48篇。     

PDMDAAC助凝PAC处理高浊度丙烯酸乳液废水

聚二甲基二烯丙基氯化铵（PDMDAAC）助凝剂主要用于低浊度天然水体的除浊,而很少用于高浓度的生产废水处理,为此,采用PDMDAAC助凝聚合氯化铝（PAC）处理高浓度丙烯酸乳液废水,考察了PAC投加量、m(PDMDAAC)∶m(PAC)、初始pH、沉淀时间对PAC混凝效果的影响,并分析了PDMDAAC的助凝机理。结果表明,PDMDAAC助凝剂对高浓度丙烯酸乳液废水混凝的处理效果明显,可以高效地去除COD和浊度。其最优混凝条件：PAC投加量为350 mg/L,m(PDMDAAC)∶m(PAC)为2%、初始pH=7.0,沉降时间为20 min。在最优混凝条件下进行中试混凝实验,废水COD由11 396 mg/L降为417 mg/L,COD去除率达到96.3%,浊度由11 220 NTU降为39 NTU,浊度去除率达到99.6%。由激光粒度和SEM分析可知,PDMDAAC助凝PAC的絮体粒径为12.4μm,PDMDAAC助凝PAC的絮凝机理更趋向于吸附电中和作用,而吸附架桥作用较弱。     

新型复合引发剂APS-TEA引发DMDAAC的聚合及PDMDAAC的应用

用一步法合成DMDAAC单体，采用APS—TEA复合引发体系引发聚合得到PDMDAAC。实验取100mL质量分数为72％的DMDAAC溶液，通N2 30min后加入APS 0．548g、TEA0．352g、EDTA·2Na 15．04mg，当反应温度为42℃，反应时间为24h时，DMDAAC的转化率为82．26％，PDMDAAC的特征粘度为1．06dL／g。采用PFS（聚合硫酸铁）、PDMDAAC和PFS—PDMDAAC复合絮凝剂处理Cu^2＋、pb^2＋浓度均为10mg／L的模拟重金属污水，PFS—PDMDAAC复合絮凝剂处理效果最好。控制模拟污水的终点DH值约为8．5，使用PFS-PDMDAAC复合絮凝剂，当PFS剂量为5．52mg／L、PDMDAAC剂量为0．39mg／L时，处理后Cu^2＋、Pb^2＋去除率分别达到99．8％和99．9％。     

PDMDAAC共聚改性用反应性单体的合成及表征

该文合成了3种具有反应性功能的单体,为获得聚二甲基二烯丙基氯化铵(PDMDAAC)改性固色剂提供基础;以二烯丙基甲基胺、二烯丙基胺、三烯丙基胺及环氧氯丙烷为原料,分别合成了(3-氯-2-羟丙基)甲基二烯丙基氯化铵(CHMDAAC)、N,N-二烯丙基-3-羟基杂氮环丁烷氯化铵(DHAC)及(3-氯-2-羟丙基)三烯丙基氯化铵(CHTAAC)等反应性功能单体,对其结构进行了分析表征,并考察了其与基准单体二甲基二烯丙基氯化铵(DMDAAC)的共聚反应性。结果表明,所得单体具有预期结构,其收率为70%～95%,且与基准单体DMDAAC间可发生有效共聚;可用于合成新的棉织物活性染料无醛固色剂用反应性PDMDAAC共聚改性聚合物。     

PDMDAAG-膨润土对活性染料废水的处理研究

以聚二甲基二烯丙基氯化铵（PDMDAAC）和钠基膨润土为原料,制备了PDMDAAC-膨润土,并与膨润土的其他改性方法进行比较,通过不同改性膨润土对活性翠蓝KN-G和活性嫩黄K-4G染料废水进行吸附,发现PDMDAAC-膨润土的吸附效果要优于其它改性方法.对实际染料废水处理的研究表明,在相同条件下,PDMDAAC-膨润土的吸附性能要略优于活性炭,PDMDAAC-膨润土在深度处理工业废水方面有广阔的前景.     

PDMDAAC/PAC/CPAM复配处理油田采出水

针对含油污水开展了聚二甲基二烯丙基氯化铵(PDMDAAC)、聚合氯化铝(PAC)、阳离子聚丙烯酰胺(CPAM)3种药剂复配实验,考察了复配组合、加药顺序、加药比例对絮凝效果的影响。结果表明：在试剂加量相同的条件下,PDMDAAC、PAC、CPAM三者复配絮凝效果要优于PDMDAAC和PAC复配以及PAC和CPAM复配,且絮体紧实;通过对比实验,PDMDAAC在PAC之前加入水样的絮凝效果较好;在有机试剂总量一定的条件下,当PDMDAAC加量4mg·L^-1、PAC加量30 mg·L^-1、CPAM加量2 mg·L^-1时,絮凝效果最好,水中悬浮物质量浓度为18.7 mg·L^-1 mg·L^-1,含油量为6.15 mg·L^-1。     

PDMDAAC在海水混凝过程中的助凝作用

将PAC与PDMDAAC协同使用处理近岸海水,考察其对海水中污染物的混凝效能,监测絮体厚度的变化过程,并分析稳定动力学规律。结果表明,与单独投加PAC相比,PAC与PDMDAAC协同作用下的絮凝效果较好,对海水中浊度和磷酸盐的去除率可分别提高22.3%、22.0%,生成的絮体厚度较大,絮凝持续时间较短,说明PDMDAAC有显著的助凝作用。从体系稳定性角度分析絮凝机理,投加PDMDAAC的海水体系具有较大的稳定动力学参数,使海水更易脱稳。     

PDMDAAC的合成及其絮凝作用的评价

以过硫酸铵为引发剂,合成了有机阳离子絮凝剂聚二甲基二烯丙基氯化铵。考察了单体始始质量分数、引发剂用量、聚合温度对聚合物转化率和特性黏数的影响。评价了不同投加量、污水温度、pH值条件对聚合物絮凝作用的影响。     

聚二甲基二烯丙基氯化铵的合成研究

本文提出了采用国产原料,经合成、精制、游离基聚合的工艺路线,来制备聚二甲基二烯丙基氯化铵。通过150t/a 装置的大批量生产,产品质量达到进口同类产品的水平,并具有工艺条件温和、收率高、产品质量稳定等优点。可替代进口产品用于石油开采、造纸等领域。     

利用矿热炉渣、矿渣、精炼渣制备复合水泥

为缓解矿渣等高活性混合材资源的紧张,通过对矿热炉渣、矿渣、精炼渣三种渣按照不同比例复掺进行了试验。试验表明,在加入激发剂后,当矿热炉渣掺量为25%、矿渣为5%、精炼渣为5%时,可配制达到PC42.5水泥;当矿热炉渣掺量为30%、矿渣为15%、精炼渣为5%时,仍可配制合格的PC32.5水泥。     

The alkali-silica reaction in alkali-activated granulated slag mortars with reactive aggregate

The expansion of alkali-activated granulated blast furnace slag (AAS) cement mortars with reactive aggregate due to alkali-silica reaction (ASR) was investigated. The alkaline activator used was NaOH solution with 4% Na₂O (by mass of slag). These results were compared to those of ordinary portland cement (OPC) mortars. The ASTM C1260-94 Standard Test Method based on the NBRI Accelerated Test Method was followed. The nature of the ASR products was also studied by SEM/EDX. The results obtained show that the AAS cement mortars experienced expansion due to the ASR, but expansion occurs at slower rate than with OPC mortars under similar conditions. The cause of the expansion in AAS cement mortars is the formation of sodium and calcium silicate hydrate reaction products with rosette-type morphology. Finally, in order to determine potential expansion due to ASR, the Accelerated Test Method is not suitable for AAS mortars because the reaction rate is initially slow and a longer period of testing is required.     

电石渣激发矿渣活性的研究

用电石渣掺量5％、9％、10％、11％、20％、25％、50％、75％制作成胶砂试块,研究电石渣对矿渣的活性激发作用。结果表明：最佳掺量比为电石渣和矿渣1：9,7d抗压强度为13.11MPa,28d抗压强度为16.29MPa。仅电石渣和矿渣掺舍时,最佳用水量为42.5g,28d抗压强度为20.71MPa。     

Resistance of alkali-activated slag concrete to acid attack

This paper presents an investigation into the durability of alkali-activated slag (AAS) concrete exposed to acid attack. To study resistance of AAS concrete in acid environments, AAS concrete was immersed in an acetic acid solution of pH=4. The main parameters studied were the evolution of compressive strength, products of degradation, and microstructural changes. It was found that AAS concrete of Grade 40 had a high resistance in acid environment, superior to the durability of OPC concrete of similar grade.     

钢渣作水泥膨胀剂的初步研究

文章介绍了国内外膨胀的发展状况和钢渣利用情况,提出把钢渣掺入水泥中作膨胀的设想并进行了一系列实验。结果表明,用钢渣用膨胀剂,膨胀龄期较长,膨胀状况良好。水泥抗压强度随钢渣掺量的增加而有所降低,水泥安全性合格。     

利用锰渣、矿渣、石灰石制备复合水泥

针对目前矿渣等高活性混合材资源的紧张,实验进行了锰渣、石灰石部分取代矿渣制备复合水泥的试验研究。研究表明,当石灰石粉掺量固定为10%时,相同水泥比例下,随着锰渣和矿渣比例的增加,胶砂试块3d强度增加,28d强度有所下降;当加入复合激发剂后复合混合材总掺量为60%,锰渣和矿渣质量比为4:1时,仍能配制合格的P.C32.5标号水泥。     

气淬钢渣制备钢渣水泥的研究

研究了气淬钢渣活性、制备钢渣水泥的方案及不同方案下制备的掺气淬钢渣水泥的物理性能及水化机理。结果表明,气淬钢渣活性指数高于普通钢渣,制备掺气淬钢渣水泥适宜采用加入激发剂或复掺水淬高炉矿渣,在激发剂作用下,气淬钢渣掺量达到50%时,其水泥强度满足P.SS32.5级水泥的要求,而普通钢渣在掺量为50%时,强度已达不到水泥的强度要求;而在复掺水淬高炉渣和气淬钢渣作用下,气淬钢渣掺量达到40%时,其水泥强度满足P.SS32.5级水泥的要求,而普通钢渣水泥强度已达不到要求;气淬钢渣用于生产高掺量、高强度等级的水泥是可行的。     

硫酸铵熔融反应法从含钛高炉渣中回收钛

以承钢含钛高炉渣、(NH₄)₂SO₄和KHSO₄为主要原料,通过熔融反应法使其中的钛转化为易溶于水的形式,达到回收钛的目的。考察了(NH₄)₂SO₄加入量、KHSO₄加入量、加热温度和保温时间对钛回收率的影响。实验结果表明,反应温度和保温时间对钛回收率的影响较大。回收钛的最适条件为：含钛高炉渣与(NH₄)₂SO₄的质量比为1∶6,反应温度为350℃,保温时间为27 min,在此条件下钛的回收率为91.7%,硫酸铵中氮的挥发损失率为81.5%。回收钛后所得残渣主要含有大量硫酸钙、二氧化硅和少量钙钛矿、钙铝黄长石。     

Activation of blast furnace slag by a new method

Blast furnace slag is used as supplementary cementing material for the production of blended cement and slag cement. Its latently hydraulic properties can be activated by several methods. Most applications employ the use of high pH values in the pore solution (> 13.0) to accelerate the corrosion of the glass network of the slag.It is shown in this work that activation is also possible by lowering the pH to a range between 11.8 and 12.2 by the addition of calcium hydroxide and soluble calcium salts. Among the salts investigated in this study are calcium chloride, calcium bromide, calcium nitrate, calcium formate, and calcium acetate. Other salts can be used alternatively as long as they are able to increase the calcium ion concentration and thus reduce the pH in the pore solution via the calcium hydroxide equilibrium. Complex formation of organic anions with calcium ions in the pore solution is a serious handicap when using organic calcium salts.This concept was tested on a particular slag improving its early compressive strength. It was possible to increase the strength of mortar bars produced from the pure slag from 3 MPa to 25 MPa after seven days by adding calcium hydroxide, calcium carbonate and calcium acetate. The early strength of slag cement containing 80% slag was increased from 6 to 16 MPa after two days by adding calcium chloride. The final strength was increased from 36 to 53 MPa after 28 days (water/cement-ratio = 0.40, 20 °C).Analytical data is included to demonstrate that application of the aforementioned concept is able to increase heat liberation and degree of slag consumption.